System for downloading and executing virtualized application files identified by unique file identifiers

ABSTRACT

A virtual process manager for use with a client application. Both the virtual process manager and the client application are installed on a client computing device. The client application is configured to receive a user command to execute a virtual application at least partially implemented by a virtualized application file stored on a remote computing device. In response to the user command, the client application commands to the virtual process manager to execute the virtualized application file. Without additional user input, the virtual process manager downloads the virtualized application file from the remote computing device and executes the virtual application at least partially implemented by the downloaded virtualized application file on the client computing device. The client application may comprise a conventional web browser or operating system shell process.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention is directed generally to a virtual process manager and more particularly, to a virtual process manager configured to download a virtualized application file from a remote server and execute the downloaded file.

Description of the Related Art

A virtual application is a virtual machine image pre-configured with all of the files, registry data, settings, components, runtimes, and other dependencies required for a specific application to execute immediately and without installation on a host computing device. The virtual application is partially isolated from other applications implemented on a host computing device and partially isolated from an underlying host operating system installed and executing on the host computing device. The virtual application is encapsulated from the host operating system by a virtual runtime environment, which includes a virtual operating system, that receives operations performed by the virtualized application and redirects them to one or more virtualized locations (e.g., a virtual filesystem, virtual registry, and the like).

Thus, the virtual application may be conceptualized as including two components: a virtualization runtime and a virtual application configuration. The virtualization runtime implements the virtual runtime environment, which implements various operating system application programming interfaces (“APIs”) in such a way that allows the executing virtual application to access and interact with items that may not be present on the host computer. The virtual application configuration includes data necessary to implement the virtual application within the virtualization runtime.

The virtual application is stored in and implemented by one or more data files and/or executable files. Depending upon the implementation details, the one or more data files and/or executable files storing and implementing the virtual application may include blocks of data corresponding to each application file of a natively installed version of the application. Herein, these blocks of data will be referred to as “virtual application files.” The one or more data files and/or executable files storing and implementing the virtual application also include configuration information. When the virtual application is executed, the configuration information is used to configure the virtual operating system to execute the virtual application. For example, the configuration information may contain information related to the virtual application files, virtual registry entries, environment variables, services, and the like. The virtual operating system is configured to communicate with the host operating system as required to execute the virtual application on the host computing device.

A download manager is a computer program that downloads files from a web server over the Internet. The download manager is separate from a web browser, which is used to navigate to a web page displaying a link to a file stored on the server. When the user clicks on the link to the file, the download manager is launched and manages the download.

Conventional download managers require user interaction and an application installation process. For example, download managers typically require a user to select a storage location on the user's computer into which the file will be downloaded. Then, after the file is downloaded, the download manager typically launches the installation process or the user executes the file separately. Alternatively, a dialog box may ask the user if the user wants to install an application implemented by the downloaded file and/or execute the file. Often, when the user indicates the user wants to execute the application, an installer is launched that installs the application. The installation process often requires additional user interactions, and may be very time consuming, require special permissions to perform the installation, and perform potentially undesirable modifications to the user's computing device. When the installer is finished, the installer may execute the downloaded (and installed) file. However, the user is typically queried a second time as to whether the user would like to execute the file.

Thus, prior art download managers require user interaction after a file is selected for download. Therefore, using conventional download managers is time consuming and requires substantial user interaction. Further, because the user must respond to the questions presented by the download manager, the user must monitor at least a portion of the file transfer.

A need exists for a virtual process manager configured to download and execute a virtual application while requiring less user interaction than prior art download managers. A further need exists for a virtual process manager that more quickly executes virtualized application files stored on a remote server particularly in view of the fact that a virtualized application file need not be installed on the user's computer to execute thereon. A method of launching applications stored on a remote server is also desirable. The present application provides these and other advantages as will be apparent from the following detailed description and accompanying figures.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a diagram of a system for transferring a virtualized application file from a server computing device to a client computing device over a network.

FIG. 2 is an illustration of a conceptualization of software components stored in a system memory of the client computing device of FIG. 1, the software components including a Client Application and a Sandbox Manager.

FIG. 3 is an illustration of a conceptualization of software components stored in a system memory of the server computing device of FIG. 1, the software components including a virtualized application file.

FIG. 4 is a flow diagram of a method performed by the Client Application of FIG. 2.

FIG. 5 is a diagram illustrating the components of the Sandbox Manager of FIG. 2.

FIG. 6 is a flow diagram of a method performed by the Sandbox Manager of FIG. 2.

FIG. 7 is a flow diagram of a method of transferring the virtualized application file from the server computing device to the client computing device over a network and/or executing the virtualized application file on the client computing device.

FIG. 8 is a diagram of a hardware environment and an operating environment in which the computing devices of the system of FIG. 1 may be implemented.

DETAILED DESCRIPTION OF THE INVENTION

The present application describes a virtual process manager (referred to as a “Sandbox Manager”) configured to download a virtualized application file from a server computing device to a client computing device operated by a user. The Sandbox Manager does not query the user for any information during the download or execution of the virtualized application file. The user simply selects the virtualized application file for download using a Client Application (such as a web browser or operating system shell) and together the Client Application and the Sandbox Manager effect the transfer of the virtualized application file to the client computing device and the execution of the virtualized application file on the client computing device. Thus, the user need not select a location in which to store the virtualized application file on the client computing device or indicate whether the user would like to execute the virtualized application file. In this manner, the Sandbox Manager may be used to download and execute the virtualized application file in less time than is required using a conventional download manager.

FIG. 1 illustrates a system 5 for downloading or otherwise transferring a virtualized application file stored on a server computing device 7 to a client computing device 9 over a network 10 (e.g., the Internet, a WAN, a LAN, a combination thereof, and the like). One or more additional computing devices, such as the computing device 11 may also be coupled to the network 10. In the embodiment illustrated, the server computing device 7 is implemented as a web server. A diagram of hardware and an operating environment in conjunction with which implementations of the server computing device 7, the client computing device 9, the network 10, and the computing device 11 may be practiced is provided in FIG. 8 and described below.

FIG. 2 illustrates a system memory 22A of the client computing device 9 (illustrated in FIG. 1) storing a conventional operating system 35A, that like most operating systems, includes a filesystem 126A, a registry 128A, and a process environment and threading subsystems component 130A. A Client Application 132 (e.g., a web browser application) and a Sandbox Manager 134 are also stored in the system memory 22A of the client computing device 9 (illustrated in FIG. 1). Optionally, as explained below, the Client Application 132 may include a plug-in 136 or similar application. In the embodiment illustrated, the Client Application 132 communicates with the Sandbox Manager 134 over a communication link 138 that may be implemented as a Transmission Control Protocol (“TCP”) connection using TCP protocol. A cache 139 may be stored on the filesystem 126A for use by the Sandbox Manager 134.

As explained above, a virtualized application file 140 is transferred to the client computing device 9 from the server computing device 7. The virtualized application file 140 is illustrated in dashed lines to indicate that the virtualized application file 140 is stored in the cache 139 during and after the download. However, before the download begins, the virtualized application file 140 is not stored in the cache 139. As will be explained below, the virtualized application file 140 may be an executable file or a file configured to execute within a virtualized environment provided by a virtual machine.

The system memory 22A stores one or more files implementing one or more virtual machines. By way of a non-limiting example, the system memory 22A may include a plurality of virtual machine executable files 137 that when executed, each implement a different virtual machine. For example, each of the virtual machine executable files 137 may implement a different version of the same virtual machine. The virtual machine executable files 137 may be executed individually. When executed, a virtual machine executable file implements a virtualized environment. Execution of a virtual machine executable file may be initiated by the Sandbox Manager 134 using a command including a parameter (e.g., a file path) identifying a virtualized application file to execute. In response to receiving the parameter, the virtual machine executable file executes the identified virtualized application file inside the virtualized environment implemented by the virtual machine executable file. The virtual machine may execute within an operating system shell process. Optionally, the virtual machine executable files 137 may be stored in the cache 139.

The virtualized application file 140 includes a version identifier that may be used by the Sandbox Manager 134 to select which of the virtual machine executable files 137 is configured to execute the virtualized application file 140.

FIG. 3 illustrates a system memory 22B of the server computing device 7 (illustrated in FIG. 1). The system memory 22B stores a conventional operating system 35B, illustrated as including a filesystem 126B, a registry 128B, and a process environment and threading subsystems component 130B. The system memory 22B stores the virtualized application file 140, which is configured to execute on the operating system 35A (see FIG. 2) of the client computing device 9 (illustrated in FIG. 1), optionally within a virtual machine implemented by a separate virtual machine executable file, without having been installed on the operating system 35A of the client computing device 9. The virtualized application file 140 may be configured to execute on the operating system 35B of the server computing device 7 (illustrated in FIG. 1), optionally within a virtual machine implemented by a separate virtual machine executable file, but this is not a requirement.

In the embodiment illustrated, the system memory 22B stores web server components 142 configured to implement a web server. The web server components 142 may be configured to provide a web page having one or more links to virtualized application files using standard http protocol. By way of non-limiting examples, the web server components 142 may include Internet Information Services (“IIS”) provided by Microsoft Corporation, Apache, and the like. While illustrated as being outside the filesystem 126B, those of ordinary skill in the art appreciate that the virtualized application file 140 and web server components 142 may be conceptualized as being within the filesystem 126B.

The virtualized application file 140 may include components necessary to implement a virtual runtime environment including a virtual operating system 120 configured to execute in the operating system 35A (see FIG. 2) of the client computing device 9 (illustrated in FIG. 1). Alternatively, the virtual runtime environment may be implemented by one of the virtual machine executable files 137 (see FIG. 2). The virtualized application file 140 includes components necessary to implement a virtual application 110 configured to execute in the virtual runtime environment. In particular embodiments, a single virtualized application file is used to implement both the virtual operating system 120 and the virtual application 110. However, those of ordinary skill in the art appreciate that more than one virtualized application file may be used to implement the virtual operating system 120 and the virtual application 110. For example, the components implementing the virtual runtime environment may be stored in one of the virtual machine executable files 137 (see FIG. 2) and the components implementing the virtual application 110 may be stored in the virtualized application file 140. Further, one or more of the files used to implement the virtual application 110 may be other than an executable file having the “exe” file extension.

The virtual operating system 120 includes a virtual filesystem 150, a virtual registry 152, and a virtual process environment and threading subsystems component 154. When executing, the virtual application 110 interacts with the virtual filesystem 150, virtual registry 152, and virtual process environment and threading subsystems component 154, instead of interacting directly with the filesystem 126A, the registry 128A, and the process environment and threading subsystems component 130A of the operating system 35A illustrated in FIG. 2. The virtual operating system 120 is configured to communicate with the operating system 35A illustrated in FIG. 2 as required to execute the virtual application 110.

The virtual application 110 executes inside a virtual runtime environment provided at least in part by the virtual operating system 120. Some virtual applications require one or more additional runtime environments to execute. For example, to execute a Flash application, the Flash runtime engine must also be installed. Therefore, to virtualize a Flash application, both the Flash application and Flash runtime engine must be included in the virtualized application file 140 and configured to execute in the portions of the virtual runtime environment provided by the virtual operating system 120. Collectively, all runtime components necessary to execute the virtual application 110 will be referred to as a virtual runtime engine. When executed, the virtual runtime engine generates, at least in part, the virtual runtime environment in which the virtual application 110 executes.

The virtualized application file 140 includes a configuration data block 121. The configuration data block 121 may include virtual application files 123A-123C corresponding to each of the application files of a natively installed version of the same application. The virtualized application file 140 identifies one or more of the virtual application files 123A-123C as a startup executable that executes when the virtual application 110 is first executed. The startup executable may be identified in the configuration data block 121.

When the virtualized application file 140 is executed, the configuration data block 121 configures the virtual operating system 120 to execute the virtual application 110. For example, the configuration data block 121 may contain configuration information related to files and directories in the virtual filesystem 150, keys and values in the virtual registry 152, environment variables, services, and the like.

The configuration data block 121 may also include basic application metadata and settings such as the application name, application version, and sandbox location. Further, the configuration data block 121 may provide isolation information to the virtual operating system 120. This information indicates which directories, virtual application files 123A-123C, virtual registry entries, environment variables, and services are to be isolated from the operating system 35A (see FIG. 2) of the client computing device 9 (see FIG. 1). While illustrated as being outside the virtual filesystem 150, those of ordinary skill in the art appreciate that the application files 123A-123C may be conceptualized as being within the virtual filesystem 150 when the virtual application 110 is executing.

To execute the virtual application 110, an initialization process is first performed. During this process, the virtual operation system 120 is launched and configured by the configuration data block 121. After the initialization process has completed, the appropriate startup executable(s) is/are launched inside the virtual operating system 120. The virtual operating system 120 intercepts calls to the operating system 35A and routes them to corresponding components of the virtual operating system 120. For example, when the virtual application 110 requests access an application file that corresponds to the virtual application file 123A using a path of a natively installed version of the application, the virtual operating system 120 intercepts the request and routes the request to one of the virtual application file 123A. The virtual operating system 120 may also route some requests and actions to the operating system 35A (see FIG. 2) of the client computing device 9 (see FIG. 1) for processing.

U.S. patent application Ser. No. 12/188,155, filed on Aug. 7, 2008, U.S. patent application Ser. No. 12/188,161 filed on Aug. 7, 2008, and U.S. patent application Ser. No. 12/685,576 filed on Jan. 11, 2010, all of which are incorporated herein by reference in their entireties, disclose systems that may be used to create and configure the virtualized application file 140. As described in greater detail in U.S. patent application Ser. Nos. 12/188,155, 12/188,161, and 12/685,576, the virtualized application file 140 may be created by a virtual application executable constructor or authoring tool 170 using an application template that includes copies of files, such as a configuration file 202, application files 111A-111C, and the like, used to configure the virtualized application file 140. However, the template is not a requirement. Instead, to build the virtualized application file 140, the authoring tool 170 needs only the configuration file 202 and copies of any applications files 111A-111C necessary for a natively installed version of the application to execute. The applications files 111A-111C, and the configuration file 202 are referred to collectively as an application configuration 171. In some embodiments, the authoring tool 170 combines the application configuration 171 and the components of the virtual runtime engine (e.g., the virtual operating system 120) into an executable virtualized application file. However, in other embodiments, the authoring tool 170 omits the components of the virtual runtime engine from the virtualized application file to create a virtualized application file for execution by a virtual machine implemented by a virtual machine executable file, such as one of the virtual machine executable files 137.

For ease of illustration, the authoring tool 170 and the application configuration 171 have been illustrated as being stored in the system memory 22B of the server computing device 7 (see FIG. 1). However, this is not a requirement. As is apparent to those of ordinary skill in the art, the virtualized application file 140 may be created on a computing device other than the server computing device 7, such as the computing device 11 illustrated in FIG. 1, and transferred to the server computing device 7 illustrated in FIG. 1 for storage thereon.

Returning to FIG. 2, as mentioned above, the system memory 22A of the client computing device 9 (see FIG. 1) stores the Client Application 132 and the Sandbox Manager 134.

Client Application

The Client Application 132 translates user commands (button clicks, etc) into requests for operations that the Sandbox Manager 134 performs. In embodiments in which the Client Application 132 is implemented as a web browser, the browser plug-in 136 or other type of translation application may be installed on the client computing device 9 (see FIG. 1). Together the browser and browser plug-in 136 perform the functions of the Client Application 132.

By way of a non-limiting example, the browser plug-in 136 may be installed on the client computing device 9 (see FIG. 1) by placing a dynamic link library (“dll”) implementing the plug-in 136 in a predetermined installation directory and registering the dll (i.e., an assembly) in the registry 128A (e.g., a Windows registry) of the client computing device 9 (see FIG. 1). An Assembly Registration tool (e.g, Regasm.exe) may be used to register the dll in the registry 128A.

Once the plug-in 136 has been installed, the plug-in can be used by a website (implemented by the web server components 142 (see FIG. 3) of the server computing device 7 illustrated in FIG. 1) via client-scripting technologies, such as client-side javascript code executing in the Client Application 132. To access the plug-in 136 from the server computing device 7 illustrated in FIG. 1, a plug-in object reference is created and sent to the Client Application 132. In response to receiving the reference to the plug-in 136, the Client Application 132 loads the plug-in by mime-type, ProgID, class GUID, and the like depending on the implementation details of the Client Application 132 (which in this embodiment, is implemented as a web browser). The plug-in 136 exposes methods which can be used to send requests to the Sandbox Manager 134.

The requests include commands and optionally, one or more parameters. The requests may be implemented as strings, each including a command. If the request also includes parameters, the parameters may be separated from one another and the command by a predetermined character, such as a semi-colon, comma, and the like. In other words, the request may be implemented as a semi-colon delimitated string or a string delimited in another manner. The following Table A provides a list of commands that my be included in a request.

TABLE A Command Parameters Description of Command ping None Commands the Sandbox Manager 134 to return a predetermined value. For example, the ping command may command the Sandbox Manager to return a pre- determined string (e.g., “TRUE”) start an Commands the Sandbox Manager 134 to application start the transfer of the virtualized identifier application file 140 identified by the application identifier to the client computing device status session Commands the Sandbox Manager 134 to identifier provide current status of the transfer of the virtualized application file 140 identified by the session identifier progress session Commands the Sandbox Manager 134 to identifier provide current progress of the transfer of the virtualized application file 140 identified by the session identifier. The progress may be indicated as percentage of the virtualized application file 140 transferred (e.g., 10%, 25%, and 100%). exec session Commands the Sandbox Manager 134 to identifier; execute the virtual application 110 and implemented at least in part by the optionally, virtualized application file 140 command-line identified by the session identifier that arguments was transferred previously to the client computing device 9 illustrated in FIG. 1

As mentioned above, the Client Application 132 communicates with the Sandbox Manager 134 over the communication link 138, which may be implemented as a TCP connection. By way of a non-limiting example, the Client Application 132 may send the requests as text messages using TCP protocol to the Sandbox Manager 134 over the TCP connection. As described above, each of the requests includes a command and may include one or more parameters (e.g., a parameter list). These commands may be characterized as a communication protocol between the Client Application 132 and the Sandbox Manager 134.

FIG. 4 provides a flow diagram of a method 200 performed by the Client Application 132 illustrated in FIG. 2. In first block 205, the Client Application 132 connects with the server computing device 7 illustrated in FIG. 1. In embodiments in which the server computing device 7 includes the web server components 142 that implement a website, and the Client Application 132 is a web browser in which the plug-in 136 is installed, in block 205, the Client Application 132 connects to the server computing device 7 over the network 10, and downloads a webpage from the website. The webpage includes a reference to the plug-in 136. When the Client Application 132 receives the reference to the plug-in 136, the Client Application 132 loads the plug-in 136.

In block 210, the Client Application 132 receives a command from the user via a conventional user interface (e.g., a mouse, keyboard, and the like). The user command instructs the Client Application 132 to download the virtualized application file 140 and/or execute the virtualized application file 140.

The plug-in 136 is configured to request a different session for each virtualized application file being transferred and/or executed. Thus, each virtualized application file being transferred and/or executed may be identified by a unique session identifier.

In decision block 212, the plug-in 136 determines whether a session identifier is associated with the virtualized application file 140. The decision in decision block 212 is “YES” when a session identifier is associated with the virtualized application file 140. The decision in decision block 212 is “NO” when a session identifier is not associated with the virtualized application file 140.

When the decision in decision block 212 is “NO,” in block 214, the plug-in 136 requests a new communication session having a unique session identifier with the Sandbox Manager 134 over the communication link 138. Then, the Client Application 132 advances to block 220.

When the decision in decision block 212 is “YES,” the Client Application 132 advances to block 220.

In block 220, the Client Application 132 translates the user command received in block 210 into a request to be sent to the Sandbox Manager 134 over the communication link 138. For example, in embodiments in which the Client Application 132 is a web browser in which the plug-in 136 is loaded, in block 210, the web browser receives the user command (e.g., the user clicks on a hyperlink, presses a button, and the like) and in block 220, the plug-in 136 translates the user command into a request including a command (e.g., one of the commands listed in Table A above) and optionally, one or more parameters (e.g., the session identifier associated with the virtualized application file 140). The user command may be an instruction to download the virtualized application file 140 (see FIG. 3), an instruction to execute the virtualized application file 140, and the like. As mentioned above, the request may be a string including the command and parameters, if any.

Returning to FIG. 4, in block 230, the Client Application 132 transmits the request to the Sandbox Manager 134 over the communication link 138 (e.g., a TCP connection) illustrated in FIG. 2. Optionally, in block 240, the Client Application 132 may receive information from the Sandbox Manager 134. The information received may be a response to the command (e.g., a response to a “ping” command), a result of performing the command, status and/or progress information related to performing a command, an error message, and the like. Then, the method 200 terminates.

Sandbox Manager

Returning to FIG. 2, the Sandbox Manager 134 receives requests from the Client Application 132 and performs the command included in the requests. The Sandbox Manager 134 manages the transfer of the virtualized application file 140 (see FIG. 3) from the server computing device 7 to the client computing device 9 illustrated in FIG. 1. The Sandbox Manager 134 also manages execution of the virtual application 110 (see FIG. 3) on the client computing device 9 (see FIG. 1). Turning to FIG. 5, the Sandbox Manager 134 includes a communications server 300 (e.g., a TCP server), one or more predefined Client Request object types 305, a Client Request Manager 310, a Downloader 315, and an Executer 320.

Returning to FIG. 4, as mentioned above, in block 214, the plug-in 136 requests a different communication session having a unique session identifier for each virtualized application file being transferred and/or executed. Referring to FIGS. 2 and 5, in response to each request for a new communication session, the communications server 300 establishes a communication session between the Client Application 132 and the Sandbox Manager 134 and generates a unique session identifier for the new communication session. In this manner, each virtualized application file being transferred and/or executed may be identified by a unique session identifier.

Each of the predefined Client Request object types 305 is associated with a particular type of virtualized application file. For example, the Client Request object types 305 include a Client Request object type associated with the virtualized application file 140. The types are used to create a Client Request object for each virtualized application file to be downloaded and/or executed by the Sandbox Manager 134. An object of the Client Request object type associated with the virtualized application file 140 is responsible for managing transfer and execution of the virtualized application file 140, including determining status, managing the cache 139 (see FIG. 2) stored on the filesystem 126A, etc.

The Client Request Manager 310 determines whether a Client Request object has been created for a particular virtualized application file associated with a session identifier. If a Client Request object has not been created for a virtualized application file, the Client Request Manager 310 (see FIG. 5) identifies which of the predefined Client Request object type is configured to manage details about the virtualized application file, creates a Client Request object of the type identified, and associates the Client Request object with the session identifier associated with the virtualized application file. By way of a non-limiting example, a Client Request object may need to be created when the Sandbox Manager 134 receives a “start” command for the first time to start downloading the virtualized application file 140. The Client Request Manager 310 may include a dictionary 330 configured to store Client Request objects for use in performing commands included in requests. The dictionary 330 may be stored in the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2).

Each of the Client Request objects includes a status field indicating a status related to the transfer and/or execution of the virtualized application file. Table B below provides non-limiting examples of status values or codes that may be stored in the status field.

TABLE B Status Code Description Not Started Transfer of virtualized application file is currently being initialized. In Progress Transfer of virtualized application file is currently in progress. Complete Transfer of virtualized application file has completed and the virtualized application file is ready to execute. Canceled Transfer of virtualized application file has been cancelled. Transfer may be canceled by a request from the Client Application 132. Alternatively, transfer of virtualized application file may be canceled by an internal operation of the Sandbox Manager 134. Error Transfer of virtualized application file has been aborted due to an error. An error code may be sent to the Client Application 132. For example, an error code may be encoded in high-order bits of a message sent in response to the “start” command. Table C below provides a non-limiting exemplary list of error codes.

The status field may be set to “Canceled” when user exits the web page (e.g., browses to another page, closes the browser window, and the like) on which the link to the virtualized application file being downloaded is displayed. By way of a non-limiting example, when the user exits the web page, a cancel call may be created automatically (e.g., by script code executing in the Client Application 132) and sent to the plug-in 136. In response, the plug-in 136 sends a cancel message including the session identifier (e.g., “cancel;<session id>”) to the Sandbox Manager 134 over the communication link 138. If the status value of the status field of the Client Request object including the session identifier in the cancel message is “In Progress,” the transfer is cancelled by the Sandbox Manager 134.

By way of a non-limiting example, the status value of the status field may be determine in the following manner. If the transfer of the virtualized application file has not yet started, the current status is “Not Started.” If the transfer has started and is in progress, the current status is “In Progress.” If the transfer has started, is not in progress, and has completed, the current status is “Complete.” If the transfer has started, is not in progress, has not completed, and has been canceled, the current status is “Canceled.” If the transfer has started, is not in progress, has not completed, has not been canceled, and has encountered an error, the current status is “Error.” Table C below provides a non-limiting example of error codes that may used by the Sandbox Manager 134.

TABLE C Error Code Description None No error occurred. Unknown An unknown error occurred. Invalid Session identifier is not valid. Session Id Network An error occurred during transfer of the virtualized application file. Invalid The source path of the virtualized application file Source (or one of its dependencies) is not valid (e.g., the path is not in the correct format).

Each of the Client Request objects includes a progress field indicating an amount (e.g., a percentage from 0% to 100%) of the virtualized application file stored in the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2).

Each of the Client Request objects may include a path to the transferred virtualized application file stored on the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2).

The Downloader 315 downloads a particular virtualized application file identified by a session identifier.

The Executer 320 executes a particular virtualized application file identified by a session identifier.

FIG. 6 provides a flow diagram of a method 350 performed by the Sandbox Manager 134 illustrated in FIGS. 2 and 5. In first block 355, the Sandbox Manager 134 receives a request from the Client Application 132. After the request is received, in block 360, the Sandbox Manager 134 parses the request to obtain the command and optionally, one or more parameters that may be included in the request. By way of a non-limiting example, in embodiments in which the request is a string, when a request from the Client Application 132 is received at the Sandbox Manager 134, the Sandbox Manager 134 parses the string to obtain the command and optional list of parameters.

Next, in decision block 365, the parameters are validated. By way of a non-limiting example, the parameters may be validated by determining whether the number of parameters matches the number that were expected. The decision in decision block 365 is “YES,” when the parameter are valid (e.g., the number of parameters matches the number that were expected). Thus, if a particular command does not include parameters (e.g., the “ping” command), the decision in decision block 365 is “YES,” if the request does not include any parameters. The decision in decision block 365 is “NO,” when the parameter are invalid (e.g., the number of parameters does not match the number that were expected).

When the decision in decision block 365 is “NO,” in block 366, an error message is sent to the Client Application 132. Then, the method 350 terminates.

When the decision in decision block 365 is “YES,” the Sandbox Manager 134 advances to decision block 367. In decision block 367, the Sandbox Manager 134 determines whether the request includes a session identifier. The decision in decision block 367 is “YES” when the request includes a session identifier. The decision in decision block 367 is “NO” when the request does not include a session identifier.

When the decision in decision block 367 is “YES,” in block 370, the session identifier is used to identify or locate a Client Request object associated with the session identifier and responsible for downloading and/or executing the virtualized application file identified by the session identifier. The dictionary 330 of the Client Request Manager 310 may be used to lookup the Client Request object associated with the session identifier.

In decision block 375, the Sandbox Manager 134 determines whether a Client Request object associated with the session identifier has been identified. The decision in decision block 375 is “YES,” when a Client Request object associated with the session identifier has been identified. The decision in decision block 375 is “NO,” when a Client Request object associated with the session identifier has not been identified in block 370.

When the decision in decision block 375 is “NO,” in block 377, the Sandbox Manager 134 sends an error message to the Client Application 132. The error message may include the error indicator “Invalid Session Id” (see Table C above). Then, the method 350 terminates. Thus, if a command is sent to the Sandbox Manager 134 with a session identifier that is not in the dictionary 330, an error is returned to the Client Application 132 and a new request must be sent to the Sandbox Manager 134. For example, if a “status,” “progress,” or “exec” command was received in block 355 including a session identifier not associated with a Client Request object, for the Sandbox Manager 134 to perform the command, the transfer must be started again with a new request including the “start” command.

When the decision in decision block 375 is “YES,” the Sandbox Manager 134 advances to block 380 described below.

When the decision in decision block 367 is “NO,” the Sandbox Manager 134 advances to decision block 385 to determine whether the Sandbox Manager 134 should create a new Client Request object. Referring to Table A above, only two commands listed do not include the session identifier: the “start” command; and the “ping” command. The decision in decision block 385 is “YES” when the command in the request is the “start” command. Otherwise, the decision in decision block 385 is “NO.” Thus, the decision in decision block 385 is “NO” when the request includes the “ping” command.

When the decision in decision block 385 is “YES,” in block 387, the Sandbox Manager 134 creates a new Client Request object and associates the new Client Request object with a session identifier. By way of a non-limiting example, a method call may be made to the Client Request Manager 310 (see FIG. 5) to create the new Client Request object. In response to the method call, the Client Request Manager 310 identifies the Client Request object type that manages details about the particular virtualized application file being transferred to and/or executed on the client computing device 9 (see FIG. 1). Then, a new Client Request object having the type identified by the Client Request Manager 310 is created.

The Client Request Manager 310 includes a Client Request object for each virtualized application file the Sandbox Manager 134 is transferring and/or executing. The Client Request object may be cached in the dictionary 330 of the Client Request Manager 310, which may be configured to provide fast lookup of the Client Request object in response to subsequent requests including the session identifier involving the cached Client Request object. The Client Request object is responsible for managing the transfer of the virtualized application file, status of the transfer, progress of the transfer, execution of the virtualized application file, management of the cache 139 (see FIG. 2), etc. Thus, when a transfer is started, a unique session identifier is generated, a Client Request object is created, the Client Request object is associated with the unique session identifier, and the Client Request object is stored in the dictionary 330 for future lookups. The status field of the new Client Request object is set to “Not Started” and the progress field is set to “0%.”

Then, the Sandbox Manager 134 advances to block 380 from block 387. When the decision in decision block 385 is “NO,” the Sandbox Manager 134 also advances to block 380.

In block 380, Sandbox Manager 134 performs the command. If applicable, the command is executed on the Client Request object identified in block 370 or created in block 387. Then, in optional block 390, Sandbox Manager 134 sends information back to the Client Application 132. For example, as discussed below with respect to the method 400 (see FIG. 7), some commands instruct the Sandbox Manager 134 to perform operations that return values to the Client Application 132. Then, the method 350 terminates.

If the command is a “ping” command, in blocks 380 and 390, the Sandbox Manager 134 sends a response to the Client Application 132. If the command is a “start” command, in block 380, the Downloader 315 downloads the virtualized application file 140. If the command is a “status” command, in blocks 380 and 390, the Sandbox Manager 134 obtains the status value from the status field of the Client Request object identified in block 370 or created in block 387 and sends the status value to the Client Application 132. If the command is a “progress” command, in blocks 380 and 390, the Sandbox Manager 134 obtains the progress value from the progress field of the Client Request object identified in block 370 or created in block 387 and sends the progress value to the Client Application 132. If the command is a “exec” command, in block 380, the Executer 320 executes the virtualized application file 140.

FIG. 7 is a flow diagram illustrating the method 400, which provides a non-limiting example of a typical communication flow between the Client Application 132 and the Sandbox Manager 134. The method 400 transfers the virtualized application file 140 (if the virtualized application file 140 is not already stored in the cache 139 illustrated in FIG. 2) from the server computing device 7 (see FIG. 1) to the cache 139 illustrated in FIG. 2 of the client computing device 9 (see FIG. 1). The method 400 then executes the downloaded virtualized application file 140 stored in the cache 139 on the client computing device 9 (see FIG. 1). The method 400 is performable automatically by the Client Application 132 and the Sandbox Manager 134 after the user has entered a single user command into the Client Application 132. Thus, the method 400 may be characterized as implementing a one-click virtualized application file download manager and Executer.

In first block 405, the Client Application 132 receives a new user command to download and execute the virtualized application file 140. In block 410, the Client Application 132 sends a request including the “ping” command to the Sandbox Manager 134. The “ping” command is sent by the Client Application 132 to determine whether the Sandbox Manager 134 is in a state to service commands (e.g., available and functioning) and capable of responding to requests. If the Sandbox Manager 134 is running and in a state to service commands, the Sandbox Manager 134 will send a response to the Client Application 132.

In decision block 415, the Client Application 132 determines whether it has received a response from the Sandbox Manager 134 to the request sent in block 410. The decision in the decision block 415 is “YES” when the Client Application 132 has received a response from the Sandbox Manager 134 indicating that the Sandbox Manager 134 is in a state to service commands and is capable of responding to requests. The decision in the decision block 415 is “NO” when the Client Application 132 has not received a response from the Sandbox Manager 134 or receives a response indicating the Sandbox Manager 134 is not in a state to service commands (e.g., available and functioning) or is incapable of responding to requests.

When the decision in the decision block 415 is “NO,” the Client Application 132 returns to block 410. Alternatively, when the decision in the decision block 415 is “NO,” the method 400 may terminate. Optionally, the Client Application 132 may display a message to the user indicating the virtualized application file 140 is not available to download.

When the decision in the decision block 415 is “YES,” in block 420, the Client Application 132 establishes a new communication session with the Sandbox Manager 134 and sends a request including a “start” command to the Sandbox Manager 134. As mentioned above, when the communications server 300 (see FIG. 5) of the Sandbox Manager 134 initiates a new session, the communications server 300 generates a new and unique session identifier. The “start” command commands the Sandbox Manager 134 to begin transferring the virtualized application file 140.

In block 425, when the Sandbox Manager 134 receives the “start” command, the Client Request Manager 310 identifies a Client Request object type for the virtualized application file 140, creates a Client Request object of the type identified, and associates the session identifier with the new Client Request object. Then, the Sandbox Manager 134 determines whether at least a portion of the virtualized application file 140 is stored in the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2). The decision in the decision block 425 is “YES” when at least a portion of the virtualized application file 140 is stored in the cache 139 (see FIG. 2). Otherwise, the decision in the decision block 425 is “NO.”

When the decision in decision block 425 is “YES,” in decision block 430, the Sandbox Manager 134 determines whether the virtualized application file 140 is stored in its entirety in the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2). The decision in the decision block 430 is “YES” when the virtualized application file 140 is stored in its entirety in the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2). The decision in the decision block 430 is “NO” when less than the entire virtualized application file 140 is stored in the cache 139 (see FIG. 2).

When the decision in decision block 430 is “YES,” the virtualized application file 140 need not be transferred to the client computing device 9 because the virtualized application file is already stored in the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2). In block 435, the Sandbox Manager 134 updates the status field of the Client Request object to “Complete” and the progress field to “100%.” Then, the Sandbox Manager 134 advances to block 440.

When the decision in decision block 425 or decision block 430 is “NO,” the Sandbox Manager 134 begins transferring the virtualized application file. If the decision block 425 was “NO,” in block 445, the Sandbox Manager 134 adds the virtualized application file 140 to the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2). The Sandbox Manager 134 sets the status field of the Client Request object to “Not Started” and the progress field to “0%.” Then, in block 450, the Sandbox Manager 134 begins transferring the virtualized application file 140 from its beginning.

If the decision block 425 was “YES” but the decision block 430 was “NO,” in block 450, the Sandbox Manager 134 sets the status field of the Client Request object to “In Progress,” calculates the progress value, and sets the progress field to the calculated progress value. Then, the Sandbox Manager 134 begins transferring the virtualized application file from wherever the previous transfer activities left off. The transfer may be started in a new thread using http protocol. In block 455, the progress field of the Client Request object is updated occasionally (e.g., periodically) to indicate the percentage of the virtualized application file 140 transferred. Then, the Sandbox Manager 134 advances to block 440.

In block 440, the Sandbox Manager 134 returns the session identifier associated with the virtualized application file 140 to the Client Application 132.

In block 460, the Client Application 132 sends a request to the Sandbox Manager 134 including the “status” command. In response to the “status” command, in block 465, the Sandbox Manager 134 sends the status value (e.g., “in progress” or “complete”) of the status field of the Client Request object to the Client Application 132. In block 467, the Client Application 132 receives the status value sent by the Sandbox Manager 134. Optionally, the Client Application 132 may display the status value of the transfer to the user.

In decision block 470, the Client Application 132 determines whether the entire virtualized application file has been downloaded. The decision in decision block 470 is “YES,” if the status field of the Client Request object indicates the entire virtualized application file has been downloaded (e.g., the status field has the value “Complete”). The decision in decision block 470 is “NO,” if the status field of the Client Request object indicates the virtualized application file 140 has not been completely downloaded (e.g., status field has the value “In Progress”).

If the decision in decision block 470 is “NO,” in block 475, the Client Application 132 sends a request to the Sandbox Manager 134 including the “progress” command to determine the progress value of the transfer of the virtualized application file 140. In response to the “progress” command, in block 480, the Sandbox Manager 134 sends the progress value in the progress field of the Client Request object (e.g., “10%,” “25%,” etc.) to the Client Application 132. In block 482, the Client Application 132 receives the progress value sent by the Sandbox Manager 134. Optionally, the Client Application 132 may display the progress value to the user. Then, the Client Application 132 returns to block 460.

If the decision in decision block 470 is “YES,” in block 485, the Client Application 132 sends a request to the Sandbox Manager 134 including an “exec” command. In response to the “exec” command, in block 490, the Executer 320 (see FIG. 5) of the Sandbox Manager 134 executes the virtual application 110 at least partially implemented by the virtualized application file 140 that the Sandbox Manager 134 has just transferred. Then, the method 400 terminates.

As mentioned above, the parameters of the “exec” command includes the session identifier (identifying the virtualized application file transferred) and optional command-line arguments. The session identifier is used to identify the Client Request Object storing the path to the transferred virtualized application file stored on the cache 139 (see FIG. 2) of the filesystem 126A (see FIG. 2). The path is then used to execute the transferred virtualized application file. The transferred virtualized application file may be executed via an operating system programming interface function call (e.g., ShellExecute, CreateProcess, and the like).

In block 490, if the virtualized application file 140 is configured to be executed inside a virtualized environment provided a virtual machine executable file (e.g., the virtualized application file 140 is not an executable file having the “.exe” extension), the Sandbox Manager 134 executes the virtual machine executable file and instructs the executing virtual machine to execute the virtualized application file 140. The Sandbox Manager 134 may send a command to the operating system 35A to execute the virtual machine inside an operating system shell process. The command may include the path to the virtualized application file 140 as a parameter that the virtual machine uses to locate and execute the virtualized application file 140.

If more than one virtual machine executable file (e.g., virtual machine executable files 137) are stored in the system memory 22A, the Sandbox Manager 134 identifies which of the virtual machine executable files 137 is configured to execute the virtualized application file 140. As explained above, the virtualized application file 140 may include a version identifier that may be used by the Sandbox Manager 134 to select which of the virtual machine executable files 137 is configured to execute the virtualized application file 140. Each of the virtual machine executable files 137 may also include a version identifier that may be matched to the version identifier of a particular virtualized application file to determine whether the virtual machine executable file is configured to execute the particular virtualized application file.

By way of a non-limiting example, blocks 425, 430, 435, 445, 450, and 455 of the method 400 may be implemented in accordance with the following block of pseudo code.

  // check filesystem cache long lTransferStartPoint = 0; string sPath = BuildCacheLocation(uriAppSource); if(File.Exists(sPath)) {  long lFullSize = FindFullSize(uriAppSource);  long lSizeOnDisk = File.GetSize(sPath);  if(lSizeOnDisk == lFullSize) {   // the app is already fully cached,   // no transfer needed   SetTransferComplete( );   return;  }  lTransferStartPoint = lSizeOnDisk; } // start the transfer StartDownload(uriAppSource, lTransferStartPoint);

By way of a non-limiting example, the function named “StartDownload” used in the above block of pseudo code may be implemented as follows:

// a function to transfer the application function void StartDownload(Uri uriSource, long lStartPoint) {  HttpWebRequest oReq = HttpWebRequest.Create(uriSource);  oReq.AddRange(lStartPoint);  HttpWebResponse oRes = oReq.GetResponse( );  Stream oStream = oRes.GetResponseStream( );  while(true) {   int iBytes = oStream.Read(aBuffer);   if(iBytes == 0) return;   WriteBufferToCacheLocation(aBuffer);   UpdateCurrentProgress( );  } }

By way of a non-limiting example, the function named “FindFullSize” used in the first block of pseudo code may be implemented as follows:

  // a function to return the full size of the // application to be transferred. function long FindFullSize(Uri uriAppSource) {  string sResponse = DoHttpHeadRequest(uriAppSource);  long lContentLength = ParseContentLength(sResponse);  return lContentLength; }

FIG. 8 is a diagram of hardware and an operating environment in conjunction with which implementations of the client computing device 9 (including the Client Application 132, the Sandbox Manager 134, the virtual machine executable files 137, and the transferred virtualized application file 140), the server computing device 7 (including the virtualized application file 140, the web server components 142, and the authoring tool 170), and the network 10 may be practiced. The description of FIG. 8 is intended to provide a brief, general description of suitable computer hardware and a suitable computing environment in which implementations may be practiced. Although not required, implementations are described in the general context of computer-executable instructions, such as program modules, being executed by a computer, such as a personal computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types.

Moreover, those skilled in the art will appreciate that implementations may be practiced with other computer system configurations, including hand-held devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. Implementations may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.

The exemplary hardware and operating environment of FIG. 8 includes a general-purpose computing device in the form of a computing device 12. Each of the client computing device 9 and the server computing device 7 may be implemented in accordance with the computing device 12. By way of non-limiting example, the Client Application 132, the Sandbox Manager 134, the virtual machine executable files 137, and the transferred virtualized application file 140 may be implemented on a first computing device like the computing device 12. The web server components 142, and the authoring tool 170 may be implemented on a second computing device like the computing device 12 configured to storing the virtualized application file 140 and generate a web page displaying a link (e.g., a hyperlink) to the virtualized application file 140 and providing a reference to the plug-in 136.

The computing device 12 includes the system memory 22. Each of the system memory 22A (see FIG. 2) and the system memory 22B (see FIG. 2) may be constructed in accordance with the system memory 22.

The computing device 12 also includes a processing unit 21, and a system bus 23 that operatively couples various system components, including the system memory 22, to the processing unit 21. There may be only one or there may be more than one processing unit 21, such that the processor of computing device 12 comprises a single central-processing unit (CPU), or a plurality of processing units, commonly referred to as a parallel processing environment. The computing device 12 may be a conventional computer, a distributed computer, or any other type of computer.

The system bus 23 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. The system memory may also be referred to as simply the memory, and includes read only memory (ROM) 24 and random access memory (RAM) 25. A basic input/output system (BIOS) 26, containing the basic routines that help to transfer information between elements within the computing device 12, such as during start-up, is stored in ROM 24. The computing device 12 further includes a hard disk drive 27 for reading from and writing to a hard disk, not shown, a magnetic disk drive 28 for reading from or writing to a removable magnetic disk 29, and an optical disk drive 30 for reading from or writing to a removable optical disk 31 such as a CD ROM, DVD, or other optical media.

The hard disk drive 27, magnetic disk drive 28, and optical disk drive 30 are connected to the system bus 23 by a hard disk drive interface 32, a magnetic disk drive interface 33, and an optical disk drive interface 34, respectively. The drives and their associated computer-readable media provide nonvolatile storage of computer-readable instructions, data structures, program modules and other data for the computing device 12. It should be appreciated by those skilled in the art that any type of computer-readable media which can store data that is accessible by a computer, such as magnetic cassettes, flash memory cards, USB drives, digital video disks, Bernoulli cartridges, random access memories (RAMs), read only memories (ROMs), and the like, may be used in the exemplary operating environment. As is apparent to those of ordinary skill in the art, the hard disk drive 27 and other forms of computer-readable media (e.g., the removable magnetic disk 29, the removable optical disk 31, flash memory cards, USB drives, and the like) accessible by the processing unit 21 may be considered components of the system memory 22.

A number of program modules may be stored on the hard disk drive 27, magnetic disk 29, optical disk 31, ROM 24, or RAM 25, including an operating system 35, one or more application programs 36, other program modules 37, and program data 38. A user may enter commands and information into the computing device 12 through input devices such as a keyboard 40 and pointing device 42. Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 21 through a serial port interface 46 that is coupled to the system bus 23, but may be connected by other interfaces, such as a parallel port, game port, or a universal serial bus (USB). A monitor 47 or other type of display device is also connected to the system bus 23 via an interface, such as a video adapter 48. In addition to the monitor, computers typically include other peripheral output devices (not shown), such as speakers and printers.

The computing device 12 may operate in a networked environment using logical connections to one or more remote computers, such as remote computer 49. These logical connections are achieved by a communication device coupled to or a part of the computing device 12 (as the local computer). Implementations are not limited to a particular type of communications device. The remote computer 49 may be another computer, a server, a router, a network PC, a client, a memory storage device, a peer device or other common network node, and typically includes many or all of the elements described above relative to the computing device 12. The remote computer 49 may be connected to a memory storage device 50. The logical connections depicted in FIG. 8 include a local-area network (LAN) 51 and a wide-area network (WAN) 52. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet. The network 10 may include any of the aforementioned networking environments.

When used in a LAN-networking environment, the computing device 12 is connected to the local area network 51 through a network interface or adapter 53, which is one type of communications device. When used in a WAN-networking environment, the computing device 12 typically includes a modem 54, a type of communications device, or any other type of communications device for establishing communications over the wide area network 52, such as the Internet. The modem 54, which may be internal or external, is connected to the system bus 23 via the serial port interface 46. In a networked environment, program modules depicted relative to the personal computing device 12, or portions thereof, may be stored in the remote computer 49 and/or the remote memory storage device 50. It is appreciated that the network connections shown are exemplary and other means of and communications devices for establishing a communications link between the computers may be used.

The computing device 12 and related components have been presented herein by way of particular example and also by abstraction in order to facilitate a high-level view of the concepts disclosed. The actual technical design and implementation may vary based on particular implementation while maintaining the overall nature of the concepts disclosed.

Returning to FIG. 2, the operating system 35A, the Client Application 132, the Sandbox Manager 134, the virtual machine executable files 137, and the transferred virtualized application file 140 may be stored as computer executable components on the system memory 22A. Each of the operating system 35A, the Client Application 132, the Sandbox Manager 134, the virtual machine executable files 137, and the transferred virtualized application file 140 may be implemented using software components that are executable by the processing unit 21 and when executed perform the functions described above.

Returning to FIG. 3, the virtualized application file 140, the web server components 142, and the authoring tool 170 may be stored as computer executable components on the system memory 22. Each of the virtualized application file 140, the web server components 142, and the authoring tool 170 may be implemented using software components that are executable by the processing unit 21 and when executed perform the functions described above.

The foregoing described embodiments depict different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected,” or “operably coupled,” to each other to achieve the desired functionality.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this invention and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this invention. Furthermore, it is to be understood that the invention is solely defined by the appended claims. It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations).

Accordingly, the invention is not limited except as by the appended claims. 

The invention claimed is:
 1. A method of downloading a plurality of virtualized application files used to execute a virtual application, the method being performed by a first computing device in communication with a second computing device over a network, the first computing device having a client application and a virtual process manager executing thereon, the second computing device storing the plurality of virtualized application files, the method comprising: at the client application, receiving a plurality of user commands to download and execute the plurality of virtualized application files stored on the second computing device, each of the plurality of virtualized application files at least partially implementing the virtual application; in response to receiving the plurality of user commands, the client application sending a plurality of first commands to the virtual process manager, each of the plurality of first commands identifying at least one of the plurality of virtualized application files and instructing the virtual process manager to download the at least one virtualized application file from the second computing device to the first computing device; at the virtual process manager, receiving the plurality of first commands sent by the client application; in response to receiving the plurality of first commands: the virtual process manager automatically determining that a first portion of the plurality of virtualized application files identified by the plurality of first commands were fully downloaded to the first computing device prior to the client application receiving the plurality of user commands, each virtualized application file in the first portion being associated with a previously generated unique file identifier, the virtual process manager automatically determining that a second portion of the plurality of virtualized application files identified by the plurality of first commands were not fully downloaded to the first computing device prior to the client application receiving the plurality of user commands, the virtual process manager automatically generating, for each virtualized application file in the second portion of the plurality of virtualized application files, a new unique file identifier and associating the new unique file identifier with the virtualized application file, the previously generated and new unique file identifiers being a plurality of unique identifiers, the virtual process manager sending the plurality of unique identifiers to the client application, and the virtual process manager automatically downloading the second portion of the plurality of virtualized application files; in response to receiving the plurality of unique identifiers and during the downloading of the second portion of the plurality of virtualized application files, the client application requesting download statuses from the virtual process manager for the plurality of virtualized application files identified in the plurality of first commands by sending status inquires to the virtual process manager, each of the status inquiries including one of the plurality of unique identifiers; providing, by the virtual process manager, the download statuses to the client application in response to the virtual process manager receiving the status inquiries; at the client application, determining that the plurality of virtualized application files have finished downloading based on the download statuses received in response to the status inquiries, and sending, to the virtual process manager, a plurality of second commands; and in response to receiving the plurality of second commands sent by the client application, the virtual process manager automatically executing the virtual application.
 2. The method of claim 1, further comprising: in response to receiving each of the plurality of first commands sent by the client application, the virtual process manager identifying a virtual machine application configured to execute the at least one virtualized application file identified by the first command, the virtual process manager executing the virtual application at least partially implemented by the at least one virtualized application file identified by the first command by executing the identified virtual machine application, and instructing the identified virtual machine application to execute the at least one virtualized application file identified by the first command.
 3. The method of claim 1, wherein in response to each of the status inquires, the virtual process manager determines status information for the at least one virtualized application file associated with the one of the plurality of unique identifiers included in the status inquiry, and sends the status information to the client application to thereby provide one of the download statuses to the client application.
 4. The method of claim 3, wherein the status information comprises a status code or a progress value.
 5. The method of claim 1, further comprising: after receiving each of the plurality of user commands, the client application requesting a session with the virtual process manager, and in response to each session request, the virtual process manager initiating a session with the client application and generating a session identifier, the session identifier being the new unique file identifier generated by the virtual process manager for one of the second portion of the plurality of virtualized application files.
 6. The method of claim 5, wherein the session is a Transmission Control Protocol (“TCP”) session.
 7. The method of claim 1, further comprising: at the client application, receiving a new user command to execute one or more of the plurality of virtualized application files stored on the second computing device after the client application has determined that each of the second portion of the plurality of virtualized application files has finished downloading; in response to the new user command, the client application sending a new download command to the virtual process manager, the new download command identifying the one or more virtualized application files and instructing the virtual process manager to download the one or more virtualized application files from the second computing device; at the virtual process manager, receiving the new download command sent by the client application; the virtual process manager determining without additional user input that the one or more virtualized application files were fully downloaded previously; and not downloading of the one or more virtualized application files in response to the new download command.
 8. The method of claim 1, further comprising: before the virtual process manager begins automatically downloading each virtualized application file of the second portion of the plurality of virtualized application files, the virtual process manager determining whether the virtualized application file was partially downloaded previously, and if the virtualized application file was partially downloaded previously, the virtual process manager downloading only a portion of the virtualized application file that was not previously downloaded.
 9. The method of claim 1, wherein the client application comprises a web browser.
 10. The method of claim 1 for use with the first computing device having an operating system, wherein the client application comprises an operating system shell process implemented by the operating system of the first computing device.
 11. A non-transitory computer-readable medium comprising instructions that when executed by a processor implement a virtual process manager configured to receive commands from a client application, the virtual process manager being configured to: receive a plurality of first commands from the client application to download a plurality of virtualized application files used to execute a virtual application, each of the plurality of first commands identifying at least one of the plurality of virtualized application files and instructing the virtual process manager to download the at least one virtualized application file; in response to receiving the plurality of first commands: automatically determine that a first portion of the plurality of virtualized application files identified by the plurality of first commands were fully downloaded previously, each virtualized application file in the first portion being associated with a previously generated unique file identifier, automatically determine that a second portion of the plurality of virtualized application files identified by the plurality of first commands were not fully downloaded previously, automatically generate a new unique file identifier for each virtualized application file in the second portion of the plurality of virtualized application files, and associate the new unique file identifier with the virtualized application file for which the new unique file identifier was generated, the previously generated and new unique file identifiers being a plurality of unique identifiers, send the plurality of unique identifiers to the client application, and automatically download the second portion of the plurality of virtualized application files; receive status inquiries from the client application in response to sending the plurality of unique identifiers to the client application and during the downloading of the second portion of the plurality of virtualized application files, each of the status inquiries including one of the plurality of unique identifiers; provide download statuses to the client application in response to the status inquiries, the client application being configured to determine when the plurality of virtualized application files have finished downloading based on the download statuses and to send a plurality of second commands to the virtual process manager after the client application determines that the plurality of virtualized application files have finished downloading, the plurality of second commands instructing the virtual process manager to execute the virtual application; and automatically execute the virtual application in response to receiving the plurality of second commands.
 12. The non-transitory computer-readable medium of claim 11, wherein in response to receiving each of the plurality of first commands from the client application, the virtual process manager is configured to: identify a virtual machine application configured to execute the at least one virtualized application file identified by the first command, wherein automatically executing the virtual application comprises executing the identified virtual machine application, and instructing the identified virtual machine application to execute the at least one virtualized application file identified by the first command.
 13. The non-transitory computer-readable medium of claim 11, wherein in response to each of the status inquires, the virtual process manager is configured to: determine status information for the at least one virtualized application file associated with the one of the plurality of unique identifiers included in the status inquiry; and send the status information to the client application to thereby provide one of the download statuses to the client application.
 14. The non-transitory computer-readable medium of claim 13, wherein the status information comprises a status code or a progress value.
 15. The non-transitory computer-readable medium of claim 11, wherein the virtual process manager is configured to receive session requests from the client application, each of the session requests requesting a session with the virtual process manager, and in response to each of the session requests, the virtual process manager is configured to initiate a session with the client application and generate a session identifier, the session identifier being the new unique file identifier generated by the virtual process manager for one of the second portion of the plurality of virtualized application files.
 16. The non-transitory computer-readable medium of claim 15, wherein the session is a Transmission Control Protocol (“TCP”) session.
 17. The non-transitory computer-readable medium of claim 11, wherein before the virtual process manager begins automatically downloading each virtualized application file of the second portion of the plurality of virtualized application files, the virtual process manager is configured to determine whether the virtualized application file was partially downloaded previously, and if the virtualized application file was partially downloaded previously, the virtual process manager downloads only a portion of the virtualized application file that was not previously downloaded.
 18. A method of downloading a plurality of virtualized application files used to execute a virtual application, the method being performed by a first computing device in communication with a second computing device over a network, the first computing device having a client application and a virtual process manager executing thereon, the second computing device storing the plurality of virtualized application files, the method comprising: receiving, by the virtual process manager, a plurality of first commands from the client application to download the plurality of virtualized application files, each of the plurality of first commands identifying at least one of the plurality of virtualized application files and instructing the virtual process manager to download the at least one virtualized application file; in response to receiving the plurality of first commands, the virtual process manager: automatically determining that a first portion of the plurality of virtualized application files identified by the plurality of first commands were fully downloaded previously, each virtualized application file in the first portion being associated with a previously generated unique file identifier, automatically determining that a second portion of the plurality of virtualized application files identified by the plurality of first commands were not fully downloaded previously, automatically generating a new unique file identifier for each virtualized application file in the second portion of the plurality of virtualized application files, and associating the new unique file identifier with the virtualized application file for which the new unique file identifier was generated, the previously generated and new unique file identifiers being a plurality of unique identifiers, sending the plurality of unique identifiers to the client application, and automatically downloading the second portion of the plurality of virtualized application files; receiving, by the virtual process manager, status inquiries from the client application in response to sending the plurality of unique identifiers to the client application and during the downloading of the second portion of the plurality of virtualized application files, each of the status inquiries including one of the plurality of unique identifiers; providing, by the virtual process manager, download statuses to the client application in response to the status inquiries, the client application being configured to determine when the plurality of virtualized application files have finished downloading based on the download statuses and to send a plurality of second commands to the virtual process manager after the client application determines that the plurality of virtualized application files have finished downloading, the plurality of second commands instructing the virtual process manager to execute the virtual application; and automatically executing, by the virtual process manager, the virtual application in response to receiving the plurality of second commands.
 19. The method of claim 18, wherein in response to receiving each of the plurality of first commands from the client application, the virtual process manager identifies a virtual machine application configured to execute the at least one virtualized application file identified by the first command, wherein automatically executing the virtual application comprises executing, by the virtual process manager, the identified virtual machine application, and instructing the identified virtual machine application to execute the at least one virtualized application file identified by the first command.
 20. The method of claim 18, wherein in response to each of the status inquires, the virtual process manager determines status information for the at least one virtualized application file associated with the one of the plurality of unique identifiers included in the status inquiry; and sends the status information to the client application to thereby provide one of the download statuses to the client application.
 21. The method of claim 20, wherein the status information comprises a status code or a progress value.
 22. The method of claim 18, wherein the virtual process manager receives session requests from the client application, each of the session requests requesting a session with the virtual process manager, and in response to each of the session requests, the virtual process manager initiates a session with the client application and generates a session identifier, the session identifier being the new unique file identifier generated by the virtual process manager for one of the second portion of the plurality of virtualized application files.
 23. The method of claim 22, wherein the session is a Transmission Control Protocol (“TCP”) session.
 24. The method of claim 18, wherein before the virtual process manager begins automatically downloading each virtualized application file of the second portion of the plurality of virtualized application files, the virtual process manager determines whether the virtualized application file was partially downloaded previously, and if the virtualized application file was partially downloaded previously, the virtual process manager downloads only a portion of the virtualized application file that was not previously downloaded. 